Optical film printing



July 30, 1940. oss 2,209,582

OPTICAL FILM PRINTING Filed May 26, 1936 3 Sheets-Sheet 1 INVENTOR EENEST Poss ATTORNEY July30,1940. I s 2,209,582

OPTICAL FILM PRINTING Filed May 26, 1936 I s Sheets-Sheet 2 INVENTOREPNEST Poss ATTORNEY July 30,1940. 5 oss OPTICAL FILM PRINTING Filedllay 26, 1936 3 Sheets-Sheet 3 I 'F'IEEL INVENTOR 512N551 Poss ATTORNEYPatented July 30, 1940 umrso STATES PATENT omcs or'rrcu. FILM rnm'rmcErnest Ross, Los Angeles, Calif., assignor, by mesne assignments, toRadio Corporation of America, New York, N. Y., a corporation of DelawareApplication May 26,1936. Serial No. 81,881

BQlaims.

is to be printed. Since this degree of shrinkage,

at times, becomes on'the order of two per cent or more, it is, animportant factor in the con-- struction of motion picture film printingapparatus. g I I Heretofore, the method usually resorted to in printingfilms of the same sizewherein the printing'film has shrunk, has beentofeed the printing and sensitized films, in superposition, over a filmfeeding sprocket member while performing the printing operation atapoint adjacent the sprocket. The printing or shrunken film is placednext to the sprocket face which has a diameter commensurate with the arcofcurvature desired to exactly compensate for the change in length ofthe printing films due to shrinkage. If the-amount of shrinkage is notexactly compensated for, as is usually the case, due to the fact thatthe arc of curvature is set for an average value, there will result aslippage between the printing and sensitized film. This slippage is dueto the difference in sprocket hole pitch between one or both of the twofilms and the pitch of the sprocket teeth which causes a slightintermittent motion of one of the films. This slippage is especiallybothersome when printing sound records of high frequencies wherein thesound wave representations may be, distorted or even cancelled'out.

One object of the present invention is to print a sensitized film from ashrunken film while compensating tor the shrinkage. This is accomplishedby providing a separate film pulledinertia controlled member, such as afiy-wheel drum, for each of the films at a point adjacent the printingapertures and driving the films past the apertures by a common sprocketor preferably by two separate synchronously driven sprockets. Aresilient film tensioning member is interposed between the sprocketmeans and the film driven fiy-wheel drum to absorb the speed variationsdue to inaccuracies in the sprocket teeth or to differences in pitchbetween the sprocketholes in the films and the sprocket teeth on therespective sprockets. Thus it will be seen that although the same numberof sprocket teeth perforations on the printing and sensitized films passthe printing points, i. e. the exposure light beam, per unit of time,the shrunken film will actually run slightly slower, this combinationtending to compensate at all times for any and all degrees of shrinkage.The interaction between the film 5 driven fiy-wheelsand the resilientfilm tension-'- ing means causes the films to move past the exposurelight at a uniform and constant speed.

As an alternative in compensating for the" shrinkage or to aid inassisting the above named mechanism, the ratio between the diameters ofthe sprocket or sprockets driving the printer, film and the sprocket orsprockets driving the sensitized film may be made commensurate with 16adapted to be employed for a film having a defi- 0 nite range ofshrinkage.

A further object of the'invention is to obviate the necessity ofrewinding a printing film at the end of each printing operation. This isaccomchange in length of the printing film due to 10 plished byproviding film driving sprockets and 26 film reels in the path of eachfilm on either side of the film driven fly-wheels. Each of the filmreels is provided-with-over-running or uni-directional clutches toimpart rotation thereof when acting as take-up reels and to produce a 30frictional drag thereon when acting as supply reels.

A further object of the invention is to prevent slippage or breakage offilm engaging a film driven inertia controlled member during accel- :5

eration or starting or the film.

This is accomplished by operatively connectdriving mechanism duringacceleration of the film and disconnecting the inertia member when 40the correct film speed is obtained.-

Referring to the accompanying drawings, Fig. 1 is a front elevationalview of a printer embodying the present invention.

Fig. 2 is a sectional plan view takeiralong the Fig. 4 is a sectionalelevational view taken along the line 4-4 of Fig. 1.

Fig. 5 is a sectional elevational view taken along the line 5-5 of Fig.4.

Fig. 6 is a sectional view through the take-up a ing the inertiacontrolledmember to the film "as comprising three main compartments, anupper film magazine compartment It, a film printing compartment ii and alower film magazine compartment l2. Each of these three'compartments maybe provided with covers or doors to permit operation of the printerwithout necessita'ting the placing of the same within a dark room.

The upper film compartment III is shown as being divided into twoseparate compartments by means of a wall 9 to house a negative orprinting film reel 13 and a positive or sensitized film reel l4. Thelower film compartment I2 is shown as beingsimilarly divided to house anegative reel 15 and a positive reel "5. Due to the 'fact that theprinting. apparatus is reversible in direction the reels l3, l4 and l5,it are adapted to alternately become supply or take-up reels, dependingupon the direction of the film through the printing compartment ll. Eachof the film reels comprises a hub I 9 on which the film is wound and arear circular flange 29.

Referring to Figs. 6 to 8, inclusive, wherein the details of themechanism of reel I3 is shown, the other mechanism being the same, reelI3 is secured to a take-up mechanism generally indicated at 22. The hubl9 and flange are secured to a shaft 23, which is Joumaled in a sleevemember 24. Sleeve member 24 is held in an apertured boss 2| formed atthe rear of the wall 21 of the compartment I0. A friction member 25slldably keyed for longitudinal adjusting movement on the outer end ofthe shaft.23 is resiliently urged by means of a spring 26' which isthreadedly secured upon the outer end of shaft 23. The friction member21 is journaled upon the outer surface of sleeve 24 and has anoverrunning clutch mechanism generally indicated at 28, providedthereon. This over-running clutch mechanism comprises a series of balls29 (Fig. 8) which are held between an outer sleeve member 30 and wedgeforming grooves 3| on the member 21, so formed that theyare adapted toing mechanism as described hereinafter. Chain Y engages a set of chainsprocket teeth .36,

. formed on the sleeve member 39. When the chain 35 is driven inthe'directlon of the arrow a, (Fig. 8), corresponding to the directionof rotation when reel i3 is employed as a take-up reel, the balls 29tend to wedge between. the grooves 3| and the inner surface of member39, thus driving this friction member 21 and, in

turn, by means of the friction between memberv 21 and member 25 drivethe film reel 13. The friction adjusting nut 26 is so adjusted that acertain amount of'slippage will occur between the members 25 and 21 toallow for compensation of the change in speed of the shaft 23 due to anincreasing diameter of the film roll upon the hub 19. A secondover-running clutch mechanism 39 is also attached to the member 21.

and comprises a wedge forming member 40 which is suitably secured to anextending sleeve portion formed on the member 21 by means of a pin 4|,

Balls 43, springs and an outer sleeve member perform the same functionas the balls29,

springs 83 and sleeve member 30 of Fig. 8. j The I sleeve member 45 issecured by' means of a bracket 46 to the wall 21. When the reel in Fig.6 acts as a supply reel, thus rotating in the direction of arrow b,(Fig. 7), the balls 43 become effective to prevent rotation of thefriction memher 21, thus the friction between members 25 and 21 preventsover-runningof the film reel.

Assuming the reels l3 and I4 to act as supply reels, the negative film48 after passing from supply reel I3 is carried through a slot 49 in theupper wall portion of the compartment II and is guided by means of idlerrollers over a buckle alarm switch roller 59. Roller 59 is secured to anarm 52, pivotally supported at it upon the rear wall 53 of thecompartment II. Operatively connected to the arm 52 is a circuit closingswitch shown by the dotted lines 53'. The arm 52 with its roller isurged in a clock-wise direction by means of a spring 55 so that in caseof film ing roller 69 and thence over a number of idler I rollers to anedge printing film gate indicated at 6|. Here the edges of the filmoutside of the sprocket tooth perforations are illuminated by means of aprinting lamp 62 which isprovided in a light-proof housing 63. A lighttube 94, preferably containing a condenser lens (not shown), is providedto transmit light from the lamp 152 to the film at 6|. A suitable maskis provided so as to allow only the outside edges of the film 48,containing footage numbers, frame lines, film identification lndicla,etc., to be illuminated. An optical system provided in the lens tube 65images the illuminated edge portions of film 48 upon the correspondingedge portions of a positive or sensitized film 96 as it passes over anidler roller 61. From the gate 6| the "negative film 48 passes onto asuitable printer lamp intensity changing device gener lly indicated at69. This device 69 may be of he usual construction wherein slots orgrooves provided on one edge of the negative film are employed toactuate a suitable switch mechanism which, in

turn, controls the current in the sound track printing lamp. I

The film after passing the device 63 engages a considerable portion offilm driven drum 19' from which the sound track portloxnof the film 49is printed onto the sound track portion of the positive sensitized film66.

Referring to-Fig. 2, the drum 19 comprises a rear fiange 1|, adapted toengage an edge portion of the film 48, and a front cup-shaped flange 12which is adapted to engage the opposite edge 1 portion of film 49. Bothof flanges 1| and 12 are secured upon a common hub 13 which is securelyfastened to a suitable shaft 14 having a fiy-wheel 15 at its outer end.Shaft 13 is journaled within a bearing 16 provided in the wall 53 ofcompartment II and within a. second bearing 11 provided on a bracket 16.v y A printing lamp 66 is secured I??? a bracket 8| which is supportedon the we by means of screws 82 and extends between H and 12 of drum 16.An opti" system provided in a lens tube 331s focuse on the sound lenstubes 65 and 33 are re-inverting so that the images from the film 36 arefocused on the film 66 in an upright manner.

From the drum 16 the negative film 33 passes over a number of idlerrollers and under an automatic tensioning and damping roller 35, similarto 66, and thence over a drive'spr'ocket 36 similar to that of 56. Fromsprocket 36 the film is led between a pair of idler rollers through aslot 81 in the lower wall portion of comp rtment II, and thence onto thereel II which serves in this instance as a take-up reel.

The positive or sensitive film 66 follows a path somewhat similar tothat of the negative film 33.

After passing from the film reel I3 it is led througha slot in the upperwall section of compartment II, under a sprocket 96, similar to that of58 but rotating in an opposite direction, and thence over an automatictensioning roller 9I similar to that of 66. The film then passes aroundidler rollers 32 and 53,'thence over roller 6?, lying directly oppositethe lens tube 65, and is finally guided by idlerrollers onto a filmdriven I drum 65.

As illustrated in. Fig. 4, the drum 35 is formed in a single piece andis secured to a shaft 36 which is journaled at one end within a bearing61, provided in the wall 53, and at its other end within a. bearing 96secured in a bracket 69. A fly-wheel I66 similar to that of 15 issecured to the shaft 96.

From the drum 65 the film 66 is led over a series of idler rollers andthence over another automatic tensioning roller III similar to that of66. Film 66 then passes over a drive sprocket I62, similar to androtating in the same direction as the upper sprocket 66. and finallypasses through a slot I63, being guided by suitable idler rollers. Thefilm is then wound on the film reel I6.

Each of the automatic tensioning and damping rollers 66, 65, 6| and IIIare ro'tatably carried on one end of an arm I35. Arm I65 is pivotally afree and continuous oscillation of the arm I65.

Referring again to Fig. 1. eachof the'arms I65, is secured to one end ofa spring 2. Spring I I2 is secured at its other end to an adjustablememher in whereby the tension .within this spring may be varied.

Although means are shown for printing only the sound track and the edgeportions, it is to e two flanges I be understood that the pictureportions may also be printed preferably by means of an optical systemsuch as that provided in lens tube 65 or by a contact printingarrangement within the Printer. 5

.Referring now to Figs. 2 to 5, inclusive, the printer mechanism isdriven by means of a single motor 1 situated at the rear of the printer.Motor H1 is connected by means of a flexible coupling 6 and shaft II6 toa spiral gear I26 10 within a lower gear box I2I. Gear I26 meshes with asecond spiralgear I22 provided on thelower end of a vertical extendingshaft I23. Av second spiral gear I23 provided on the shaft I23 engages aspiral gear I25 at either side thereof. One of these gears I is providedon each of a pair of sprocket shafts I26 and I21, journaled in the gearbox I2I. and having the lower film sprockets 86 and I62, respectively,(Fig. 1) secured to the forward ends thereof. These sprockets l6 and I62are thus rotated in opposite directions but at equal speeds in relationto each other. Shaft I23 is connected by means of a flexible couplingI29 to a vertically extending shaft I23 having its upper end journaledwithin a gear box I36. A spiral gear "I secured at the upper end ofshaft I23, within the gear box I36, meshes with a pair of spiral gearsI32 and I33 on either side thereof.. Gears I32 and I33 are secured tosprocket shafts I33 and I35, respectively, which are journaled in thegear box I36.

Shafts I33 and I35 have secured at their forward ends the film sprockets56 and 66, respectively. The sprocket shaft I33 has a pair of chain assprockets I36 and I31 secured thereto at its rear end (Figs. 3 and 4)which are adapted to drive a set of chains I38 and I39, respectively.Chains I38 and I39 drive the sprocket teeth 36 formed on the take-upmechanisms of the reels I3 and- I 3, respectively. The second set ofchain 46 sprockets I32 and 633 are secured upon the lower sprocket shaftI26 and drive a set of chains I36 and I, respectively. Chains I36 and Iare adapted to drive the sprocket teeth provided on the take-upmechanisms of the lower reels I5 and I6, respectively.

I will now describe the means for setting the film drums 16 and 65 andtheir respective fiywheels 15 and I66 into motion at the beginning ofthe printing operation. Fly-wheels 15 and I66 50 are provided with gearteeth I36 and I31. The gear teeth I36 and I31 are adapted to mesh withidler gears I38 and 6 which in turn are driven by gears I56 and IN,respectively, secured to the ends the sprocket shafts I26 and I21,respectively. The gears I38 and I36 are Journaled upon stud members E52and I53. respectively. These stud members are secured to boxes I55 andI56 extending from the body portion of the lower gear box I2I. Gears I36and I36 are adapted to slide in or out of mesh with the sets of gearteeth I36 and I31 on the fiy-wheels 15 and I66 respectively, whilecontinuously meshing with the gears I56 and I5I, respectively. GroovesI51 and I58 cut i the gears us and m (Figs. 2 and 4) are engaged by theupper ends of a pair of'levers I56 and I66 (Fig. 5) respectively. Lowerends of levers I56 and I66 are secured upon a single,

transverse shaft I6I, which is journaled in bear- A rod I61 slidablelongitudinally within bearings 7 placed in the circuit of the motor I".

formed in the wall it and inthe lower portion of the bracket I 66, has aset of rack teeth I84 which mesh with the gear I65. By pressing a buttonI69 formed on the outer end oi! shaft I61, rotation of gears I65 and I64is effected which in turn causes the idler gears I44 and I48 to meshwith the gear teeth I 46 and I" on fiy-wheels I5 and I00, respectively.A spring I interposed between the button I68 and the wall 53 urgesthe'rod 51 outwardly and c nsequently causes the two gears I48 and I44to ove out of mesh with the-fly-wheel teeth when pressure is released onthe button I49. A switch "I is provided adjacent the end of the rod I41which switch is I In the operation of the starting button I69, the rodI61, through gears I64 and I45, first causes the gears I44 and I49 tomesh with the fiy-wheel teeth and then, on further movement of thebutton I49. causesthe switch ill to close the motor circuit and thusstart the motor I ii.

A hand-wheel I12 is secured to the motor shaft I13 of motor III to allowmanual rotation of the printer mechanism for'threading of the film andalso to align the teeth of'gears I48 and I49 with the fiy-wheel teethI45 and I41, respectively, to permit meshing. A suitable relay (notshown) is provided in conjunction with the switch I to P rmit the motorcircuit to remain closed after the starting button I69 has beenretracted through the action of spring I'IiI.

' A braking mechanism generally indicated at I (Figs. 2 and 3) isprovided to stop the rotation of the film driven fly-wheels I5 and I00and their accompanying film drums It and 95, re-

spectively, when the motor circuit isopened. A bracket I'IG situatedbetween the two fly-wheels I5 and IIID forms a sliding bearing foravertically reciprocal red I", the lower end I78 of which forms a plungerwhich is adapted to be acted upon by a solenoid I19. A pair of brakeshoes I80 and I8I are supported at the upper end of the bracket I16 andare adapted to slide horizontally within sets of ways I82 and I83 formedthereon. Apair of'links I84 and I85 iorming a toggle joint connect thebrake shoes.

- I44 and I8I to the vertical bar I". Whenthe upwardly and thus retractsthe brake shoes I44 and I4I away from; the" fly-wheeis I4 and I44 whenno current is passing through he brake solenoid I14. Pairs of balancingsprings I44 and I44 secured between the brake shoes I44 and I4I hold theshoes in correct alignment. A stop" button I44 (Fig. 1) is provided toactuate a suitable switch (notshown) which in turn opens the motorcircuit and simultaneously closes the solevnoid so as to apply a brakingrorce to 'the fiywheelsfand their respective film driven drums.

When the button In is allowed to be retracted the solenoid circuit 'isalso opened. v A suitable reversing switch (not shown) provided' in themotor circuit to reverse the direction-of rotation of motor I"and-consequently the rotation or the printer mechanismso' as toselectively drive the upward or downward fliroiigh'the printer. 7

Having thus described the invention, .what is" claimed as new anddesired secure by letters Patent, is:

1. A film printer comprising a plurality of vertically arrangedcompartments, a plurality of supply reels in the upper compartment, a'plurality of takeup reels in the lower compartment, a plurality offilm-pulled drums in an intermediate compartment, one of said drumsbeing hollow, a light source within said hollow drum, an optical systemfor projecting light from said hollow drum to said other drum, and meansfor advanclng'a plurality of films from the upper compartment to thelower compartment over said drums, said advancing means being alsoadapted to advance said films from said lower compartment to said uppercompartment. n

2. A film printer comprising a vertical panel divided into a pluralityof vertical sections divided into horizontally disposed compartments,means for supplying and taking up films in the upper and lower sectionsof said panel, means .in an intermediate panel for advancing-negativeand positive films from said upper to said lower sections or from saidlower to said upper sections, said negative film being confined to oneseries of vertical compartments and said positive film to another seriesof vertical compartments, a plu- I rality of film-pulled drums in saidintermediate section, one of said drums-being hollow, a light source insaid hollow drum, an' optical system for projecting light from said,hollow drum to said other drum, and film tensioningmeans disposed oneither side of said drums te -enable the said films to be operated .ineither direction with equal "eficiency.

,3. A film printer adapted to optically print a positive film from anegative film, a vertical panel for said printer having three sectionsdivided into two horizontally arranged compartments,

means in an intermediate section for advancing films from the upper tothe lower compartments and from the lower compartments to the upper theupper and lower sections of which include supply and takeup reelsalternatively, means in an. intermediate section for driving said filmseither upwardly or downwardly in synchronism,

' film-pulled drums and flywheels positioned in said intermediatesection having their axes in 'substantially the same horizontal plane, adrive shaft for said 'film advancing means, and means forinterconnecting said drive shaft with said flywheels for actuating saidflywheels-and drums during acceleration thereof, said means beingadapted to disconnect said shaft from said fiywheels when uniform speedofsaid flywheels has been attained. v

5. A film printer arranged substantially symmetrically about the centerof a vertical panel, an upper section or said panel housing supply andtakeup reels alternately and a lower "section of said panels housingsupply and takeup reels alternately, a plurality of sprockets in thesamevertical plane adapted to advance said films from top to bottom orfrom bottom to top synchronously with respect to the numberof frames ofsaid films, a vertical drive shaft for operating said sprockets and saidtakeup reels, film-pulled drums having respective flywheels attachedthereto and having their axes located in substantially the samehorizontal p1ane,'a motor for actuating said drive shaft, and means formanually interconnecting said drive shaft with said flywheels duringacceleration of said printer and for disconnecting said flywheels fromsaid drive shaft after uniform speed has been attained.

6. A film printer comprising a panel, film supply reels for said panel,film takeup reels for said panel, asplurality of sprockets for advancinga v plurality of films from said supply reels to said takeup reels, 9.pair of film-pulled drums, said sprockets pulling said films over saiddrums, one of said drums being hollow, a light source in one of saiddrums, an optical system for projecting light from said hollow drum tothe other 01' said drums, said drums having respective flywheelsattached thereto for stabilizing the movement of said films over saiddrums, a motor for driving said sprockets, and means for directlyconnecting said motor with 'said flywheels during acceleration thereofand for disconnecting said flywheels from said motor after said motorhas attained uniform speed.

ERNEST ROSS.

